subs. phr. (common).—A person of heart but no manners.

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  1753.  The Adventurer, No. 64. He married a lady, whose influence would have polished the ROUGH DIAMOND by degrees.

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  1853.  BULWER-LYTTON, My Novel, V. xiv. And believe me, though I’m a ROUGH DIAMOND, I have your true interest at heart.

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